H'mm, that makes sense. I tend to imagine that police officers are specially trained to remember details of faces, something I am extraordinarily bad at doing because I am so busy processing them into a snap impression about someone's character and/or mood. ("Ummm, no, officer... well, he was white, and, er, probably in his early twenties... I think he had light hair, but don't quote me on that, and he looked thoroughly cheesed off.") But in the circumstances I'm sure you're right.